Blood lead levels of secondary school students in Dhaka, Bangladesh after the elimination of leaded gasoline and phase-out of two-stroke vehicles: study on one hundred children

Abstract

Background: Lead (Pb) is a proven environmental toxicant throughout the world. Elevated blood lead level (BLL) adversely affects the neuro-cognitive and behavioral development of children. Considering the worst source of lead pollution, the government of Bangladesh banned leaded petrol and phased out two-stroked vehicles from Dhaka citya€”the capital of Bangladesha€”in late 1999. In 2000, on the verge of introducing unleaded gasoline, a baseline survey showed high mean value of BLLs (15 µg/dL) in school children of Dhakaa€”much higher than the CDC's permissible level of 10 µgm/dL. Methods: This cross sectional, follow-up study was conducted to see the current status of BLLs in school children of Dhaka city. Total 100 students from two schools, 50 girls and 50 boys from grade six through ten, were randomly selected and their finger-pricked bloods were analyzed for Pb levels. Results: The mean (±SD) BLLs was 15.31±5.81 µgm/dL; and the majority (84%) of the students tested had BLLs higher than 10µg/dL. The BLLs was found significantly higher among the students who used to play outside house premises in a dusty environment (p=0.03) and among the frequent users of a traditional eye cosmetics a€A“surmaa€ (p= 0.032). No significant associations were noted between BLLs and the gender of the study subjects, their housing status, and the distance of the houses from the school. Conclusion: The mean BLL is still alarmingly high in the studied school children that have not declined significantly despite taking several visibly effective measures. Recommendation: The possible causes and source(s) of such persistently higher BLLs in children need priority exploration, since this important environmental health issue is of crucial importance so far the health and wellbeing of the future generations of the country are concern.